Pub Date : 2021-01-01DOI: 10.1177/1178622120982590
T. Doolotkeldieva, S. Bobusheva, Mahabat Konurbaeva
Currently, in the territory of Kyrgyzstan, 50 storage facilities of obsolete pesticides exist; they store about 5000 tons of these hazardous chemicals. The storage conditions have become unusable for a long time. They pose a serious threat to the people living there, livestock, and the environment. The main purpose of this research was the use of selected bacteria with cytochrome P450 genes for the bioremediation of polluted soils around the burial sites in model soil experiments. In the first trial of biodegradation experiments, one contaminated soil was used without any changes in chemical contents, and in the second, the physical and chemical contents of the soil were improved to maintain the bioremediation conditions. The soils in both variants were treated 3 times (ie, once a month) with suspensions of a single culture or a blend of active bacteria (1 × 108 cells/mL) selected from in vitro biodegradation experiments. Two control units without the addition of the bacteria culture were also run. The quantification of targeted persistent organic pollutants (POPs) before and after biodegradation was performed by capillary gas chromatography (GC) coupled to a mass spectrometer. In 6 months, obsolete pesticides such as dieldrin, α-endosulfan, β-endosulfan, and 4-heptachlor-epox pure were able to degrade almost completely, up to 98% to 99.0%, by the blend of bacteria and the single culture of bacteria. Endrin aldehyde showed more resistance as the blend of bacteria was able to degrade it to 59.77%. To improve the aerobic degradation for elimination of pesticides from contaminated soils, it is necessary to create optimal agrotechnical and agrochemical conditions.
{"title":"The Improving Conditions for the Aerobic Bacteria Performing the Degradation of Obsolete Pesticides in Polluted Soils","authors":"T. Doolotkeldieva, S. Bobusheva, Mahabat Konurbaeva","doi":"10.1177/1178622120982590","DOIUrl":"https://doi.org/10.1177/1178622120982590","url":null,"abstract":"Currently, in the territory of Kyrgyzstan, 50 storage facilities of obsolete pesticides exist; they store about 5000 tons of these hazardous chemicals. The storage conditions have become unusable for a long time. They pose a serious threat to the people living there, livestock, and the environment. The main purpose of this research was the use of selected bacteria with cytochrome P450 genes for the bioremediation of polluted soils around the burial sites in model soil experiments. In the first trial of biodegradation experiments, one contaminated soil was used without any changes in chemical contents, and in the second, the physical and chemical contents of the soil were improved to maintain the bioremediation conditions. The soils in both variants were treated 3 times (ie, once a month) with suspensions of a single culture or a blend of active bacteria (1 × 108 cells/mL) selected from in vitro biodegradation experiments. Two control units without the addition of the bacteria culture were also run. The quantification of targeted persistent organic pollutants (POPs) before and after biodegradation was performed by capillary gas chromatography (GC) coupled to a mass spectrometer. In 6 months, obsolete pesticides such as dieldrin, α-endosulfan, β-endosulfan, and 4-heptachlor-epox pure were able to degrade almost completely, up to 98% to 99.0%, by the blend of bacteria and the single culture of bacteria. Endrin aldehyde showed more resistance as the blend of bacteria was able to degrade it to 59.77%. To improve the aerobic degradation for elimination of pesticides from contaminated soils, it is necessary to create optimal agrotechnical and agrochemical conditions.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1178622120982590","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48400664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1177/11786221211010702
P. Martínez-Austria, José Alejandro Jano-Pérez
Climate change is one of the greatest threats that our civilization is facing because increases in extreme temperatures severely affect humans, the economy, and ecosystems. General circulation models, which adequately predict climate change around the world, are less accurate at regional levels. Therefore, trends must be locally assessed, particularly in regions such as the Baja California Peninsula, which is a thin mass of land surrounded by the Pacific Ocean and the Gulf of California. Herein, we discuss extreme temperature trends in the Baja California Peninsula and whether they are statistically significant based on the Spearman’s nonparametric statistical test. For these purposes, 18 weather stations covering the entire region were analyzed, revealing that maximum temperatures for the hottest months are rising at a rate that is consistent with the RCP 8.5 scenario. Changes in minimum temperatures were also analyzed.
{"title":"Climate Change and Extreme Temperature Trends in the Baja California Peninsula, Mexico","authors":"P. Martínez-Austria, José Alejandro Jano-Pérez","doi":"10.1177/11786221211010702","DOIUrl":"https://doi.org/10.1177/11786221211010702","url":null,"abstract":"Climate change is one of the greatest threats that our civilization is facing because increases in extreme temperatures severely affect humans, the economy, and ecosystems. General circulation models, which adequately predict climate change around the world, are less accurate at regional levels. Therefore, trends must be locally assessed, particularly in regions such as the Baja California Peninsula, which is a thin mass of land surrounded by the Pacific Ocean and the Gulf of California. Herein, we discuss extreme temperature trends in the Baja California Peninsula and whether they are statistically significant based on the Spearman’s nonparametric statistical test. For these purposes, 18 weather stations covering the entire region were analyzed, revealing that maximum temperatures for the hottest months are rising at a rate that is consistent with the RCP 8.5 scenario. Changes in minimum temperatures were also analyzed.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/11786221211010702","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45052019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1177/11786221211026577
W. Sebnie, E. Adgo, H. Kendie
Understanding soil types of a given area is an important prerequisite to design optimum management strategies such as irrigation water management. The study was thus conducted on characterization and classification of Zamra irrigation scheme in Abergelle district of Amhara Region, which has an area of 196.16 ha. For this study, 53 auger observations, four profile pits, extensive visual observations, reconnaissance survey, and descriptions of soil profiles and laboratory analysis were used to study the morphological and physicochemical properties of the soils of the scheme. Twelve disturbed and undisturbed soil samples were collected from all profiles of each genetic horizon for laboratory analysis. The soils of the study area were identified based on Food and Agricultural Organization of the United Nations/World Reference Base for Soil Resources (FAO/WRB) 2015. The results revealed that the textural classes of all profiles of the study site ranged from sandy clay loam to sandy loam. The chemical properties of the soil in terms of total nitrogen, organic matter, and available phosphorus were in the very low and low categories as per the criteria developed by Tekalign and Olsen, respectively, whereas exchangeable bases (Ca, Mg, K, and Na), cation exchange capacity, and extractable micronutrients (Fe, Mn, Zn, and Cu) were medium to high. Based on morphological, physical, and chemical analyses, the soils were classified as Leptic Regosols (Eutric, Loamic; 21.99% of the area), Vertic Cambisols (Hypereutric; 17.87%), Haplic Regosols (Eutric; 36.69%), and Rhodic Nitisols (Eutric; 23.44%). Therefore, management techniques that enhance soil fertility (including crop rotations, manuring, fallow periods, proper management of crop residues, and leguminous cover crops) and water-saving technologies suitable to the terrain of the area are the best options to enhance land productivity in the area.
{"title":"Characterization and Classification of Soils of Zamra Irrigation Scheme, Northeastern Ethiopia","authors":"W. Sebnie, E. Adgo, H. Kendie","doi":"10.1177/11786221211026577","DOIUrl":"https://doi.org/10.1177/11786221211026577","url":null,"abstract":"Understanding soil types of a given area is an important prerequisite to design optimum management strategies such as irrigation water management. The study was thus conducted on characterization and classification of Zamra irrigation scheme in Abergelle district of Amhara Region, which has an area of 196.16 ha. For this study, 53 auger observations, four profile pits, extensive visual observations, reconnaissance survey, and descriptions of soil profiles and laboratory analysis were used to study the morphological and physicochemical properties of the soils of the scheme. Twelve disturbed and undisturbed soil samples were collected from all profiles of each genetic horizon for laboratory analysis. The soils of the study area were identified based on Food and Agricultural Organization of the United Nations/World Reference Base for Soil Resources (FAO/WRB) 2015. The results revealed that the textural classes of all profiles of the study site ranged from sandy clay loam to sandy loam. The chemical properties of the soil in terms of total nitrogen, organic matter, and available phosphorus were in the very low and low categories as per the criteria developed by Tekalign and Olsen, respectively, whereas exchangeable bases (Ca, Mg, K, and Na), cation exchange capacity, and extractable micronutrients (Fe, Mn, Zn, and Cu) were medium to high. Based on morphological, physical, and chemical analyses, the soils were classified as Leptic Regosols (Eutric, Loamic; 21.99% of the area), Vertic Cambisols (Hypereutric; 17.87%), Haplic Regosols (Eutric; 36.69%), and Rhodic Nitisols (Eutric; 23.44%). Therefore, management techniques that enhance soil fertility (including crop rotations, manuring, fallow periods, proper management of crop residues, and leguminous cover crops) and water-saving technologies suitable to the terrain of the area are the best options to enhance land productivity in the area.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/11786221211026577","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45075449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.1177/1178622120988318
E. Bandala, J. Rodrigo‐Comino, M. T. Latif
With over 64.1 million cases worldwide (by December 1, 2020) and a death toll surpassing 1.48 million the COVID-19 pandemics has filled not only with fear and isolation our day-to-day lives but also with a significant amount of disinformation, the unreliability of data, and lack of trust on the response of governmental officers and authorities that, sadly, can be translated in loss of lives in our closest circles (colleagues, friends, family). At Air, Soil and Water Research (ASW), we believe that knowledge is the only way out of this and any other crisis faced by humankind, and our team has been working elbow-to-elbow (but online) to offer the best quality research and scientific knowledge that will certainly assist for better decision making and led towards the best path to get us through this so hard time.
{"title":"2021: The New Normal and the Air, Soil and Water Research Perspective","authors":"E. Bandala, J. Rodrigo‐Comino, M. T. Latif","doi":"10.1177/1178622120988318","DOIUrl":"https://doi.org/10.1177/1178622120988318","url":null,"abstract":"With over 64.1 million cases worldwide (by December 1, 2020) and a death toll surpassing 1.48 million the COVID-19 pandemics has filled not only with fear and isolation our day-to-day lives but also with a significant amount of disinformation, the unreliability of data, and lack of trust on the response of governmental officers and authorities that, sadly, can be translated in loss of lives in our closest circles (colleagues, friends, family). At Air, Soil and Water Research (ASW), we believe that knowledge is the only way out of this and any other crisis faced by humankind, and our team has been working elbow-to-elbow (but online) to offer the best quality research and scientific knowledge that will certainly assist for better decision making and led towards the best path to get us through this so hard time.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1178622120988318","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45078511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.1177/1178622120975829
J. Kamińska, E. Lucena-Sánchez, G. Sciavicco
Anthropogenic environmental pollution is a known and indisputable issue, and the importance of searching for reliable mathematical models that help understanding the underlying process is witnessed by the extensive literature on the topic. In this article, we focus on the temporal aspects of the processes that govern the concentration of pollutants using typical explanatory variables, such as meteorological values and traffic flows. We develop a novel technique based on multiobjective optimization and linear regression to find optimal delays for each variable, and then we apply such delays to our data to evaluate the improvement that can be obtained with respect to learning an explanatory model with standard techniques. We found that optimizing delays can, in some cases, improve the accuracy of the final model up to 15%.
{"title":"Temporal Aspects in Air Quality Modeling—A Case Study in Wrocław","authors":"J. Kamińska, E. Lucena-Sánchez, G. Sciavicco","doi":"10.1177/1178622120975829","DOIUrl":"https://doi.org/10.1177/1178622120975829","url":null,"abstract":"Anthropogenic environmental pollution is a known and indisputable issue, and the importance of searching for reliable mathematical models that help understanding the underlying process is witnessed by the extensive literature on the topic. In this article, we focus on the temporal aspects of the processes that govern the concentration of pollutants using typical explanatory variables, such as meteorological values and traffic flows. We develop a novel technique based on multiobjective optimization and linear regression to find optimal delays for each variable, and then we apply such delays to our data to evaluate the improvement that can be obtained with respect to learning an explanatory model with standard techniques. We found that optimizing delays can, in some cases, improve the accuracy of the final model up to 15%.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1178622120975829","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47113805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-01DOI: 10.1177/1178622120978203
S. Kanchanasuta, S. Sooktawee, A. Patpai, P. Vatanasomboon
Particulate matter (PM) less than 2.5 micron (PM2.5) issue is 1 of the important targets of concern by the United Nations’ Sustainable Development Goals. Bangkok is a megacity and facing air pollution problems. This study analyzed PM, PM2.5 and PM less than 10 micron (PM10), monitoring data from stations located in Bangkok, and aimed to present their variations in diurnal, weekly, and intra-annual timescales. High PM concentrations are related to calm wind. The diurnal variation of PM2.5/PM10 suggested a greater accumulation of PM2.5 than PMcoarse during the low wind speed. Potential source areas affecting PM rising at each monitoring station were identified using statistical technique, bivariate polar plot, and conditional bivariate probability function. Results showed that Ratchathewi District Monitoring Station identified 3 potential source areas related to emissions from transportation sources creating rising PM concentrations. The first potential source was located in the northwest direction, namely, the Rama VI Road close to the conjunction with Ratchawithi Road. The second potential source area was located around the cross-section between Phaya Thai Road and Rama I Road, while the third was located at the intersection of the Phaya Thai Road to Yothi Street and Rang Nam Road. These potential source areas constitute useful information for managing and reducing PM.
{"title":"Temporal Variations and Potential Source Areas of Fine Particulate Matter in Bangkok, Thailand","authors":"S. Kanchanasuta, S. Sooktawee, A. Patpai, P. Vatanasomboon","doi":"10.1177/1178622120978203","DOIUrl":"https://doi.org/10.1177/1178622120978203","url":null,"abstract":"Particulate matter (PM) less than 2.5 micron (PM2.5) issue is 1 of the important targets of concern by the United Nations’ Sustainable Development Goals. Bangkok is a megacity and facing air pollution problems. This study analyzed PM, PM2.5 and PM less than 10 micron (PM10), monitoring data from stations located in Bangkok, and aimed to present their variations in diurnal, weekly, and intra-annual timescales. High PM concentrations are related to calm wind. The diurnal variation of PM2.5/PM10 suggested a greater accumulation of PM2.5 than PMcoarse during the low wind speed. Potential source areas affecting PM rising at each monitoring station were identified using statistical technique, bivariate polar plot, and conditional bivariate probability function. Results showed that Ratchathewi District Monitoring Station identified 3 potential source areas related to emissions from transportation sources creating rising PM concentrations. The first potential source was located in the northwest direction, namely, the Rama VI Road close to the conjunction with Ratchawithi Road. The second potential source area was located around the cross-section between Phaya Thai Road and Rama I Road, while the third was located at the intersection of the Phaya Thai Road to Yothi Street and Rang Nam Road. These potential source areas constitute useful information for managing and reducing PM.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1178622120978203","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44967536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-01DOI: 10.1177/1178622120971251
Daniela Oliveira da Silva, Bruna Hayashida Arôxa, V. Klausner, E. Bastos, A. Prestes, A. Pacini
We report a study of the particulate matter emissions related to the 2015 fire outbreak at a fuel tank storage facility located at Santos, a coastal city in Brazil. The facility, managed by the company Ultracargo, had oil tanks (filled with gasoline and ethanol) destroyed by fire that lasted more than a week, between 2nd and 9th April. In this article, we present the atmospheric concentration analysis of particulate matter (PM10) measured over the entire month of April 2015 by the 2 closest stations that integrate the air quality monitoring system of the São Paulo State Environmental Company (CETESB). The results were compared with similar data from the same period of the yesteryear (April 2014). The results were also complemented by the air masses trajectories over the region (obtained with HYSPLIT/NOAA software). Our results do indicate a subtle increase in the particulate concentration during the days of the fire, followed by a fast dissipation over the subsequent weeks. The observed plume dispersion discussion is made considering the meteorological patterns of the region and other environmental and health reported impacts related to the accident.
{"title":"Report of Particulate Matter Emissions During the 2015 Fire at Fuel Tanks in Santos, Brazil","authors":"Daniela Oliveira da Silva, Bruna Hayashida Arôxa, V. Klausner, E. Bastos, A. Prestes, A. Pacini","doi":"10.1177/1178622120971251","DOIUrl":"https://doi.org/10.1177/1178622120971251","url":null,"abstract":"We report a study of the particulate matter emissions related to the 2015 fire outbreak at a fuel tank storage facility located at Santos, a coastal city in Brazil. The facility, managed by the company Ultracargo, had oil tanks (filled with gasoline and ethanol) destroyed by fire that lasted more than a week, between 2nd and 9th April. In this article, we present the atmospheric concentration analysis of particulate matter (PM10) measured over the entire month of April 2015 by the 2 closest stations that integrate the air quality monitoring system of the São Paulo State Environmental Company (CETESB). The results were compared with similar data from the same period of the yesteryear (April 2014). The results were also complemented by the air masses trajectories over the region (obtained with HYSPLIT/NOAA software). Our results do indicate a subtle increase in the particulate concentration during the days of the fire, followed by a fast dissipation over the subsequent weeks. The observed plume dispersion discussion is made considering the meteorological patterns of the region and other environmental and health reported impacts related to the accident.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1178622120971251","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48089036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-01DOI: 10.1177/1178622120969190
James Peter Muchoka, Daniel Njiru Mugendi, Paul Nthakanio Njiruh, C. Onyari, Paul Kamau Mbugua, Ezekiel Mugendi Njeru
The use of arbuscular mycorrhizal fungi (AMF) to enhance soil phosphate uptake is a biological technique considered to cure phosphate deficiency in soils. This study investigated association of Aspilia pruliseta Schweif shrub with AMF in Kenya. The study aims at profiling a tropical shrub with multiple ecological benefits that could reduce addition of chemical phosphatic fertilizer into the soil and reverse negative consequences of eutrophication. Sampling was purposive to have areas with or without Aspilia pruliseta vegetation growing. A small amount (10 g) of the soil from 27 composite samples was used for spore count determination and a similar amount for next generation sequencing. Spore counts varied significantly among soil textural types, sample locations, and soil depth. Sandy loam had the highest spore counts with a mean average of 404 spores. The spore count decreased significantly (P < .05) with the depth of soil from a mean of 514 spores to 185 along the rhizosphere. The intensity of spore morphotypes was significantly higher at P < .05 for soils whose vegetation was covered with Aspilia pruliseta than those without. Aspilia pruliseta vegetation used together with sandy loam soil could culture commercial mycorrhiza fungi production for use in agrisystems.
{"title":"Arbuscular Mycorrhizal Fungi Colonization in the Rhizosphere of Aspilia pruliseta Schweif. ext Schweif in the Semiarid Eastern Kenya","authors":"James Peter Muchoka, Daniel Njiru Mugendi, Paul Nthakanio Njiruh, C. Onyari, Paul Kamau Mbugua, Ezekiel Mugendi Njeru","doi":"10.1177/1178622120969190","DOIUrl":"https://doi.org/10.1177/1178622120969190","url":null,"abstract":"The use of arbuscular mycorrhizal fungi (AMF) to enhance soil phosphate uptake is a biological technique considered to cure phosphate deficiency in soils. This study investigated association of Aspilia pruliseta Schweif shrub with AMF in Kenya. The study aims at profiling a tropical shrub with multiple ecological benefits that could reduce addition of chemical phosphatic fertilizer into the soil and reverse negative consequences of eutrophication. Sampling was purposive to have areas with or without Aspilia pruliseta vegetation growing. A small amount (10 g) of the soil from 27 composite samples was used for spore count determination and a similar amount for next generation sequencing. Spore counts varied significantly among soil textural types, sample locations, and soil depth. Sandy loam had the highest spore counts with a mean average of 404 spores. The spore count decreased significantly (P < .05) with the depth of soil from a mean of 514 spores to 185 along the rhizosphere. The intensity of spore morphotypes was significantly higher at P < .05 for soils whose vegetation was covered with Aspilia pruliseta than those without. Aspilia pruliseta vegetation used together with sandy loam soil could culture commercial mycorrhiza fungi production for use in agrisystems.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1178622120969190","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45167360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-01DOI: 10.1177/1178622120969658
Yohannis Fetene, T. Addis
Phosphorous from municipal and industrial wastewater is the main cause of eutrophication of rivers and lakes, because effluent quality from conventional secondary wastewater treatment plants does not meet the discharge standard that demands further treatment. Therefore, we investigated pumice as a potential low-cost adsorbent for the tertiary treatment of phosphate from municipal wastewater. The phosphate adsorption process reached equilibrium after 60 minutes contact time and achieved a removal efficiency of 94.4% ± 0.7% for an adsorbent dose of 10 g/L in 3 mg/L phosphate solution. The highest phosphate removal was recorded at pH 7. The experimental data best fitted with the Redlich-Peterson isotherm and the pseudo-second-order kinetic models. The coexisting anions decreased phosphate adsorption in the order of mixture >SO42– > HCO3− > NO3− > Cl− > CO3−. Pumice removed 95% ± 0.2% of phosphate from effluents of the secondary treatment unit of a municipal wastewater treatment plant. Furthermore, effective regeneration of saturated pumice was possible with a 0.2 M NaOH solution. Therefore, pumice could be a technically workable low-cost reusable adsorbent for phosphate removal from wastewater as a tertiary treatment to curb eutrophication of surface waters. However, further column adsorption study is recommended for a continuous flow system to optimize process design variables and scale up for field applications.
{"title":"Adsorptive Removal of Phosphate From Wastewater Using Ethiopian Rift Pumice: Batch Experiment","authors":"Yohannis Fetene, T. Addis","doi":"10.1177/1178622120969658","DOIUrl":"https://doi.org/10.1177/1178622120969658","url":null,"abstract":"Phosphorous from municipal and industrial wastewater is the main cause of eutrophication of rivers and lakes, because effluent quality from conventional secondary wastewater treatment plants does not meet the discharge standard that demands further treatment. Therefore, we investigated pumice as a potential low-cost adsorbent for the tertiary treatment of phosphate from municipal wastewater. The phosphate adsorption process reached equilibrium after 60 minutes contact time and achieved a removal efficiency of 94.4% ± 0.7% for an adsorbent dose of 10 g/L in 3 mg/L phosphate solution. The highest phosphate removal was recorded at pH 7. The experimental data best fitted with the Redlich-Peterson isotherm and the pseudo-second-order kinetic models. The coexisting anions decreased phosphate adsorption in the order of mixture >SO42– > HCO3− > NO3− > Cl− > CO3−. Pumice removed 95% ± 0.2% of phosphate from effluents of the secondary treatment unit of a municipal wastewater treatment plant. Furthermore, effective regeneration of saturated pumice was possible with a 0.2 M NaOH solution. Therefore, pumice could be a technically workable low-cost reusable adsorbent for phosphate removal from wastewater as a tertiary treatment to curb eutrophication of surface waters. However, further column adsorption study is recommended for a continuous flow system to optimize process design variables and scale up for field applications.","PeriodicalId":44801,"journal":{"name":"Air Soil and Water Research","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/1178622120969658","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48387274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-01DOI: 10.1177/1178622120970954
Oscar D. Máynez-Navarro, M. Méndez-Rojas, D. X. Flores-Cervantes, J. Sánchez-Salas
Advanced oxidation processes based on photocatalytic generation of •OH radicals have emerged as promising technologies for the removal of recalcitrant pollutants in water. However, their poor recyclability has reduced their potential large-scale application. Herein, a Fe3O4-embedded ZnO system has been prepared and its photocatalytic •OH radicals activity was evaluated by monitoring the photo-assisted bleaching of p-nitrosodimethylaniline (pNDA). Water disinfection performance was determined by measuring Escherichia coli inactivation under different conditions. Bleaching of nearly 80% of the initial pNDA concentration after just 120 minutes under UV365nm irradiation was determined. Bacterial inactivation at different concentrations (0.1, 1.0, and 5.0 mg mL−1) of the Fe3O4/ZnO nanocomposite was determined, finding that the best performance was obtained at 0.1 mg mL−1 (90%) just after the first 30 minutes under UV irradiation. The materials are easily magnetically recovered and their performance evaluated after 3 consecutive cycles of reuse. These magnetic and photoactive nanocomposites showed improved performance and could be used for wastewater treatment or disinfection processes of water.
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